Various products are made and stored on rolls, reels, spools, etc. The weight and size or these products can make them unmanageable. Illustrative of such products are rolls of sheet metal, wire, newsprint and bales of hay. A number of apparatus, many with a central probe device, have been made to maneuver these awkward/heavy products. This central probe device allows the lifting and reorienting of, in effect, anything with a central aperture; further examples being well casings and pipe tubing.
One such prior art structure uses a vacuum center lift device to hold the material onto the hollow center core by withdrawing air from between layers of sheet material.
Another prior art structure uses an expandible probe which is inserted into the hollow center of the roll, or reel or the like, thereby retaining the product on the probe.
A third prior art structure uses a lifting device wherein a probe is inserted into the hollow center core of the product in question. This probe uses a sleeve and tooth device whereby teeth from the probe are available to project into the center core of the product upon movement of the sleeve. This sleeve movement allows the teeth to pop up from the probe device and bite into the product core to retain the product on the probe. This prior art structure additionally uses a single actuator arm mechanism for pivoting the probe to maneuver the product when the probe is received in its hollow core.
A problem encountered with the retention of the product on the probe has been the canting of the sleeve device relative to the probe resulting in axial locking of the sleeve. A bias against the teeth causing the teeth to become held firmly in either the up or down position regardless of the intention of the operator can, thereby, result.
Another problem encountered with the retention function has been overmovement of the sleeve apparatus relative to the probe allowing the probe teeth to withdraw too far within the probe. Consequently, the teeth projections are left without means to effect their extension. Further sleeve manipulation no longer results in activation of the teeth to the outward position.
A problem encountered with the lifting and maneuvering of the product derives from the often significant weights thereof. The weight of the product is often too great for the power of the lifting device.
The present invention provides apparatus to overcome these difficulties.